The present invention relates to an invasive medical apparatus for restoring patency to occluded vessels. In particular, the present invention is a clinically practical rotational angioplasty system.
In U.S. Pat. No. 4,445,509 entitled METHOD AND APPARATUS FOR REMOVAL OF ENCLOSED ABNORMAL DEPOSITS which issued to David C. Auth on May 1, 1984, the concept of flexibly conveying high-speed rotational energy through a catheter which can, in turn, be threaded into an artery obstructed by pathological material was described. In the same patent, the concept for differential cutting was introduced as a means of aggressively removing hard deposits while sparing soft normal tissue.
In U.S. Pat. No. 4,646,736 entitled TRANSLUMINAL THROMBECTONY APPARATUS issued Mar. 3, 1987, the concept of winding, and thereby ensnaring, fibrin to destructure and dissolve an intravascular clot, and a machine designed for that purpose, was described. In U.S. patent application Ser. No. 816,190, entitled TRANSLUMINAL MICRODISSECTION DEVICE, filed Jan. 6, 1986, now abandoned the concept of producing non-clogging fragments of soft or hard tissue was described.
In U.S. Pat. No. 4,679,557 entitled ELECTRODYNAMIC TRANSLUMINAL ANGIOPLASTY SYSTEM, issued Jul. 14, 1987 by Eric A. Opie, et al. a complete system, employing a prime mover, a control device, and an angioplasty cutting head of the type described in U.S. Pat. No. 4,445,509, is described. That system, though, was designed with a frictional drive prime mover, and it is not suitable for use with a very high speed abrasive burr, of the type described in Ser. No. 816,190. Accordingly, a single, clinically practical device, having a high speed drive, a rotating, ablative burr, a suitable controller, and the ability to remove fibrin and clear clots, which could be conveniently used in a sterilized environment, would be highly desirable.